Hydrolysis of aryl halides with metal phosphates

ABSTRACT

ARYL HALIDES, SUCH AS CHOROXYLENE, ARE HYDROLYZED TO THE CORRESPONDING RING HYDROXYLATED ARYL COMPOUNDS, SUCH AS XYLENOL, BY CONTACTING THE ARYL HALIDES AND STREAM WITH A RARE EARTH METAL PHOSPHATE CATALYST, SUCH AS LANTHANUM PHOSPHATE, CERIUM PHOSPHATE AND NEODYMIUM PHOSPHATE. A METHOD OF PREPARING THE RARE EARTH METAL PHOSPHATE IS ALSO DISCLOSED. THE ADDITION OF SMALL AMOUNTS OF COPPER GREATLY IMPROVES THE ACTIVITY OF THE RARE EARTH METAL PHOSPHATE OR YTTRIUM PHOSPHATE FOR THE HYDROLYSIS REACTION.

United States Patent 3,838,182 HYDROLYSIS 0F ARYL HALIDES WITH METAL PHOSPHATES William L. Kehl and Raymond J. Rennard, Jrn, Pittsburgh, Pa., assignors to Gulf Research & Development Company, Pittsburgh, Pa.

No Drawing. Continuation-impart of application Ser. No. 103,003, Dec. 30, 1970, now Patent No. 3,752,878. This application Feb. 25, 1971, Ser. No. 118,940

lint. Cl. 07c 37/02 US. Cl. 260-629 28 Ciaims ABSTRACT OF THE DTSCLOURE This applicatiorfis a continuation-in-part of our copend ing Ser. No. 103,003, filed Dec. 30, 1970, now U.S. Pat. No. 3,752,878, entitled Hydrolysis of Aryl 'Halides With a Rare Earth Metal Phosphate, and assigned to the same assignee as the present application.

This invention relates to a process for the hydrolysis of aryl halides to ring hydroxyl substituted aryl com pounds using metal phosphates as the catalyst. This invention also relates to a method of preparation of such metal phosphate and to the addition of copper as a promoter.

A new group of materials has now been discovered which promotes the hydrolysis of aryl halides.

In accordance with one aspect of the invention, an aryl halide is hydrolyzed to produce a ring hydroxyl substituted aryl compound by a process which comprises contacting the aryl halide in the presence of steam with a catalyst comprising at least one rare earth metal phos phate. By a rare earth meta in this application is meant at least one rare earth metal selected from the group consisting of lanthanum, cerium and neodymium. Commercially available mixtures of lanthanides are also meant to be included in the term rare earth metal with the understanding that the lanthanide portions of these mixtures consist primarily of compounds of lanthanum, cerium and neodymium but may also contain small amounts (usually less than ten percent) of compounds of the other lanthanides such as praseodymium and those elements in the Periodic Table having atomic numbers from 62 to 71. By the term rare earth metal phosphate is meant pri marily (over 90 percent) a rare earth metal orthophosphate.

The charge stock can be any aryl halide. By an aryl halide. is meant any aryl compound having at least one halide selected from the group consisting of chlorine, bromine and iodine directly attached to a ring carbon atom. The aryl halide suitably has from one to two aromatic rings which may be condensed or uncondensed and have from one to six halide substituents. Preferably, the aryl halides have from one to two rings, condensed or uncondensed, and from one to two halide substituents. Most preferably the aryl halides are single ring aromatic monohalides. The aryl compounds can suitably have from six to 20 carbon atoms, preferably six to ten carbon atoms, and can have other substituents such as alkyl groups and N0 groups. The alkyl substituents preferably are the so-called lower alkyl groups having from one to four carbon atoms, most preferably methyl. In fact,

it is one of the surprising features of this invention that the catalysts described herein are so effective in promoting the hydrolysis of alkylated aryl halides such as chlorotoluene and chloroxylenes.

The preferred aryl halides can be represented by the formula:

Ra R2 where R R R R R and R are selected from the group consisting of chlorine, bromine, iodine, lower alkyl groups, hydrogen and N0 where at least one of said substituents is selected from the group consisting of chlorine, bromine and iodine. The preferred compounds represented by the above formula are those wherein only one of the substituents is represented by chlorine, bromine or iodine and from zero to two of the remaining substituents is a lower alkyl group, preferably methyl,

and wherein the remaining substituents are hydrogen.

A list of suitable aryl halides for use in the process of this invention include, but are not limited to, the following: chlorobenzene; monochlorotoluenes, i.e., 1-chloro-2- methylbenzene, 1 chloro3-methylbenzene and l-chloro- 4 methylbenzene; monochloroxylenes, i.e., 1-chloro-2,3-

dimethylbenzene, 1-chloro-2,4-dimethylbenzene, l-chloro- 2,5 dimethylbenzene, 1 chloro 2,6 dimethylbenzene,

1 chloro 3,4 dimethylbenzene and 1-chl0ro-3,5-di

phosphates are also suitable catalysts for this reaction.

The rare earth metal phosphates are preferably used as catalysts in their unsupported form. However, if desired, the catalysts can be deposited on a suitable support material.

The rare earth metal phosphate can be represented by the general formula given below:

MePOu,

where Me has a valence of plus three and can be lanthanum, cerium, neodymium or mixtures thereof. The preferred rare earth metal phosphates to employ are lanthanum and cerium. As noted above, mixtures of the rare earth metals can also be employed in their phosphate form to catalyze the subject reaction, and mixtures are also preferred for economic reasons since mixtures of rare earth metals which can be converted to the desired phosphate form are available commercially. As noted above, these mixtures can contain minor amounts, about ten percent or less, of other lanthanides.

The novel methods of preparation of the rare earth metal phosphates will be defined later in the specification. The aryl halide hydrolysis reaction occurs according to the general equation given below:

aryl halide H2O aryl 0H H-halide catalyst where the aryl halide is as defined above and the catalyst employed is as defined below. It is necessary, of course, that water be present, and the volume ratio of water to halogenated aryl charge stock is usually about 0.5 :l to

Patented Sept. 24, 1974 2: 1. The volume ratio of water to aryl halide is, however, not critical and can suitably be from 0.1:1 to :1 or more, for example, 100:1 or more, but is preferably from 0.511 to 2:1 for economic reasons. Sufiicient water should be present to satisfy the stoichiometric requirements of the reaction as indicated by the above equation.

Any suitable hydrolysis reaction conditions can be employed. For example, hydrolysis conditions can include a temperature range of from about 300 to about 600 C., preferably from 375 to 500 C. Below 300 C. the reaction is too slow to be of economic interest, whereas at temperatures above 600 C. the amount of coke byproduct produced increases and thus decreases the selectivity of the reaction to form the desired hydroxylatcd aromatics. When coke is produced it tends to react with the steam under the conditions of the reaction to produce hydrogen which in turn reacts with the aryl halide to give the corresponding aryl compound plus HCl. The reaction pressure is preferably atmospheric but can be from 0.5 to 2.0 atmospheres when the preferred vapor phase reaction occurs. The liquid hourly space velocity of the aryl halide is suitably from 0.1 to 2.0, but is preferably from 0.3 to 1.0 volumes of aryl halide per volume of catalyst per hour.

The reaction is very simple and occurs by passage of the aryl halide, preferably in vapor form, together with water, usually as steam, under the conditions of reaction in the proper amount through a bed of the rare earth metal phosphate catalyst. The products are cooled, collected and separated by conventional techniques. A fluid bed operation can also be employed if desired.

The rare earth metal phosphates of this invention can be prepared by any suitable method. Certain methods have been found to be particularly desirable in forming the more active forms of the rare earth metal phosphates. The rare earth metal phosphates prepared in accordance with the procedures to be described below are primarily or substantially the orthophosphate form of the metals.

In accordance with the invention, a rare earth metal phosphate is prepared by a process which comprises forming a first aqueous solution of a rare earth metal salt; forming a second aqueous solution of a phosphate ion source having the formula:

X H PO where X can be NH or a monovalent alkali metal and where a has a value from zero to three and b has a value of three minus a; and contacting the first and second aqueous solutions to precipitate the desired rare earth metal phosphate at a pH in the combined solutions of about 1.0 to 5.5.

It is preferred in the above procedure that the first and second solutions be added continuously to a stirred precipitation zone in an amount such that the molar ratio of the rare earth metal to the phosphate ion is from 1:1 to 1:3, preferably from 1:1 to about 1:15.

In the alternative, a batch process can be operated wherein the phosphate ion solution is added slowly to the rare earth metal salt solution to precipitate the metal phosphate and the addition of the phosphate ion solution continued until the pH of the combined solutions is from 5.5 to 8.0, preferably 5.5 to 6.5.

The more active forms of the LaPO compositions made in accordance with the methods of this invention have X-ray diffraction patterns and infrared absorption spectra which indicate the LaPO has a structure which appears to be intermediate between the structure for the hexagonal and monoclinic forms of LaPO which are described in the literature (see R. C. L. Mooney, ACTA Crystallographica, Volume 3, Page 339, for the hexagonal data and R. C. L. Mooney, J. Chem. Physics, Volume 16, Page 1003 [1948]) or which perhaps more properly can be described as a disordered monoclinic structure.

Any rare earth metal salt which is soluble in the solvent from which the desired metal salts can be precipitated can suitably be employed. Usually the solvent is water, although aqueous solutions of acids, such as nitric acid, can also be employed as well as acetone and alcoholic solutions of the metal salts. Suitable rare earth metal salts include, but are not limited to, the nitrates; chlorides; and salts such as the oxides or oxide hydrates, which, when dissolved in acid solutions, form, for example, the nitrates and chlorides. The most preferred salts are the nitrates, as any residual nitrate salts can be decomposed by heating whereas the chlorides must be more carefully removed by added washings.

Examples of suitable rare earth metal salts which can be employed include, but are not limited to: lanthanum nitrate; cerium nitrate; neodymium nitrate; lanthanum chloride; cerium chloride; neodymium chloride; commercially available (La 03 'XH20,

where RE is a mixture of other lanthanides; commercially available (La-RE)Cl -6H O, where RE is a mixture of other lanthanides; and RE(NO -5H O, where RE is a mixture of lanthanides.

The phosphate ion source can be any water soluble phosphate having the formula:

X H PO where X can be NH, or a monovalent alkali metal and where a has a value from zero to three and b has a value of three minus a.

The preferred phosphate ion source is one wherein X is NH, and more preferred when X is NH; and a has a value in solution of at least two.

Examples of suitable phosphate ion source compounds include, but are not limited to: (NH PO (ammonium phosphate); (NH HPO (dibasic ammonium hydrogen phosphate); (NHQH PQ, (monobasic ammonium dihydrogen phosphate); H PO (phosphoric acid); (Na) PO (sodium phosphate); (K) PO (potassium phosphate); Na i-IP0 (sodium hydrogen phosphate); NaH PO (sodium dihydrogen phosphate); KH PO (potassium dihydrogen phosphate).

In preparing the rare earth metal phosphates from the rare earth metal salt and phosphate source, appropriate solutions of both components are prepared and the solutions are contacted together to form the desired precipitate. In the continuous process, the molar ratio of the phosphate ion to the rear earth metal cation is at least 1:1. In a batch process, the phosphate source solution is always added to the rare earth metal cation solution, and thus the initial molar ratio of phosphate ion to rare earth metal cation is very low, but the final molar ratio is at least 1:1.

The appropriate solutions of rare earth metal salt and phosphate ion, usually aqueous, can be contacted at any suitable temperature and pressure, and ambient conditions are usually employed. Temperatures within the range of 5 C. to C. can, however, suitably be employed as well as pressures from subatmospheric to p.s.i.g. or more.

It is important for the preparation of the desired rare earth metal phosphates that the pH of the precipitation medium be carefully controlled. In general, the pH of the precipitation medium should be from 1.0 to 5.5 during precipitation of the bulk of the rare earth metal phosphate. Thereafter, the pH may be increased by the addition of a suitable alkaline material to a level from 5.5 to 8.0, usually 5.5 to 6.5. Suitable examples of alkaline materials include, but are not limited to: NH OH, alkali metal hydroxides such an NaOH, KOH and NH gas.

The rare earth metal phosphates can suitably be prepared in a batch process or, preferably, in a continuous process.

BATCH PROCESS In a batch process, the phosphate ion source solution is added slowly with vigorous stirring to minimize pH gradients to the rare earth metal salt solution. Preferably, the pH of the rare earth metal salt solution is initially adjusted to a level of about 4.5 to 5.0 by the addition of acid, such as HNO if a nitrate salt is used. The pH of the phosphate ion source solution is adjusted to a level of 7.5 to 9.5 by the addition of an alkaline material such as NH OH or urea, or by the addition of NH gas which forms NH OH in situ.

In the preferred form where the rare earth metal nitrate is employed and the phosphate source is (NH HP'O or (NH )H P0 the addition of the phosphate solution to the nitrate salt solution results in a lowering of the pH of the combined solutions since HNO is formed which ionizes to lower the pH as per the following equation using lanthanum nitrate as an example:

As the rare earth metal phosphate precipitates, the pH continues to decrease until all of the rare earth metal salt has been converted to the phosphate. The pH of the solution will obviously thereafter increase if the addition of the (NH HPO is continued. The final mole ratio of rare earth metal to phosphate ion is suitably from 1:1 to 1:3 in the solution.

For reasons which are not understood, metal phosphates which are more active for the hydrolysis reaction result When the pH of the combined solutions is maintained while precipitation is occurring at some constant pH value within the range of 2.5 to 4.0 after such value is initially reached. The pH can suitably be maintained at a desired constant level by the addition of an alkaline material such as NH OH or NH gas. After the precipitation of the metal phosphate is complete, the pH may be allowed to increase to a level of 5.5 to 8.0, usually 5.5 to 6.5, before separation of the precipitate.

CONTINUOUS PROCESS In the preferred continuous process for the preparation of the metal phosphates, portions of the rare earth metal salt solution and phosphate ion source solution having pHs Within the range shown above for the batch process are added together in a ratio such that the pH of the resulting combined solutions decreases. If the phosphate source solution has a pH of greater than nine and is added in a greater than 1:1 proportion to the rare earth metal salt solution having a pH of about 4.7, then the pH of the combined solutions tends to increase and the desired precipitate is not formed. If the phosphate source has a pH of about 7.5 to 9.0, then it can suitably be added in a molar ratio slightly greater than 1:1 to the rare earth metal salt solution and the pH of the combined solutions decreases and results in the precipitation of the desired phosphate. Once the pH level decreases to a value within the range from 5.0 to 2.0, the molar ratio of the phosphate source solution to the rare earth metal salt solution can be increased, if desired, so long as the pH is maintained at some value, preferably a constant value, within the range of 5.0 to 2.0, preferably 4.0 to 2.5. There is, of course, continuous and vigorous mixing as the two solutions enter the precipitation zone to reduce as much as possible any pH gradient in the precipitation zone.

The concentration of rare metal salt in the starting solutions for either batch or continuous operation is not critical and can be any value where the salt stays in solution under the conditions of the reaction. Preferably a dilute solution of salt is used, such as a concentration of 2.0 to 15.0 weight percent salt, so as to more easily control the pH gradient in the combined solutions by vigorous stirring.

The concentration of phosphate ion source material in the starting phosphate ion source solution is similarly not critical but for similar reasons is suitably from 1.5 to 20 weight percent.

It is further preferred in the continuous operation to adjust the pH of the initial rare earth metal salt and phosphate ion solutions as described above for the batch operation and then continuously monitor the pH of the combined solutions and to maintain the pH at some desired constant pH level within the range of 5.0 to 2.0 throughout the remainder of the addition step when such desired pH level is reached. The desired pH level should be attained as quickly as possible after the start of the addition step by the use of proper proportions of the initial salt and phosphate ion solutions. It is further preferred in the continuous operation to add the rare earth metal salt and phosphate ion solutions relatively fast to effect rapid crystallization of the rare earth metal phosphate. Further, the molar ratio of the rare earth metal to the phosphate ion is suitably within the range from about 1:1 to 1:3, but is preferably about 1:1 to 121.5. The pH level can be maintained by the addition of a suitable alkaline material as noted above in connection with the batch process. The pH can be monitored by any suitable method known in the art, and the particular method of monitoring is not critical. Suitable pH monitoring meters are available commercially.

Usually in a continuous operation a relatively small vessel is employed as the precipitation zone. Vigorous stirring is employed and the desired metal phosphate precipitates almost immediately on the addition of the two streams into the precipitation zone. To aid in this, the two solutions are added to the precipitation Zone in close proximity to each other and to the mixing means. A continuous overflow is normally maintained and aliquot portions of the precipitate and mother liquor are removed to a holding Zone where the pH is adjusted by the addition of a suitable alkaline material to a level of 5.5 to 8.0, usually 5.5 to 6.5 prior to separation of the precipitate from the mother liquor. Usually the pH is adjusted in the holding zone shortly after the precipitate enters the holdin-g zone which is usually within five minutes to five hours.

In addition, it has been found that ammonium phosphate is most conveniently obtained by passing NH gas into a dilute solution of H PO (1.5 to 20 Weight percent H PO in water) whence the hydrogen in the acid is replaced by NH A continuous series of ammonium phosphate products is obtained as more and more of the hydrogen is replaced. This is reflected in an increase in the pH of the solution as the NH; content is increased. It is preferred to add NH gas until the pH is in the range of 8.0 to 9.0, most preferably about 8.7, and to use this solution as the phosphate ion source.

The rare earth metal phosphate precipitate can then be suitably separated by filtration or centrifugation, washed with Water to remove Water-soluble salts such as NH NO if such is formed, and dried under suitable conditions such as a temperature of to C. in air. The dried phosphate can be calcined to activate it for catalytic purposes such as for the hydrolysis of aryl halides as described herein. Suitable calcination temperatures include a temperature from 500 to 800 0., preferably 550 to 650 C., for a time of from four to 24 hours or more.

The invention will be further described with reference to the following experimental work. All hydrolysis experiments were carried out by using a 22" x 4" internal diameter tubular quartz reactor heated by means of a furnace completely surrounding the vertically placed tube.

The temperatures in the catalyst bed were controlled using a thermo-electric temperature regulator. Internal temperatures were measured by means of a concentric thermocouple well running the length of the reactor. The aryl halide feed and water were introduced into the reactor separately using calibrated syringe pumps. Water was pumped into a stainless steel steam generator where is was vaporized and heated to 300 C'. The aryl halide TABLE I feed was preheated and mixed with the steam at the top of the reactor. The top eight inches of the reactor were packed with alundum pellets to serve as a preheat zone. Example 2 3 4 5 6 7 For product analysis the total efiluent from the reactor was condensed in an ice trap. The aqueous and organic phases were then dissolved in a sufiicient amount of acetone to give a single phase. This solution was analyzed Hydrolysis of o-chlorotoluene using a LaPO 4 catalyst Reaction temp., C.... 500 475 475 450 425 425 Volume ratio liquid 1120 to liquid 0- 2 2 2 2 2 2 LHSV O. 291 0. 291 0. 582 0. 201 0. 201 0. 201 Time, minute 120 120 120 120 120 360 chromatographically using a Varian 1500 temperature Conversion 24.4 23.6 15.3 18.0 12.8 12.4

. a programmed hydrogen flame detector. Gaseous products 1 33:2 231 2g: g 23% g g were analyzed by mass spectrometry. The catalysts were ILHSV r h l 1 I d I regenerated between experiments in air at reaction tembased g gg g-g Space W m hm 0t m perature The pressure in all runs wa atmospheric and 2 Conversion in this application 111813.115 the weight percent aryl halide converted to all products except coke. the llquld hourly Space veloclty of the y hallde was 3 Selectivity in this application means the weight percent of reacted about 0 to 0 3 15 aryl halide going to the desired hydroxylated aryl compounds.

' Y1cldin this applicationmeansyicld of hydroxylated aryl compounds Example 1 calculated by multiplying conversion times selectivity.

The catalyst for this example was prepared as follows: A series of runs was then made using the catalyst of (1) 144 grams /3 mole) of La(NO -6H O was dis- Example 1 which was calcined at 600 C. The results solved in 100 cc.s of distilled water (pH=4.7); are shown in Table II below.

TABLE II Hydrolysis of various aryl halides using a LaPOi catalyst Example number 8 9 10 11 12 Charge aryl halide ohlorotoluene..- o-Chlorotoluene... Chlorobenzene.... m-Chlorotoluene p-Chlorotoluenc. Reaction temperature, C 500 475 475 475 475. Volume ratio liquid H20 to liquid aryl halidc 2 2.. LHSV 0. 291. Tin1e,1ninntes. 120... Convcrsi0n 25.2.. Selectivity..- 86.4.. Yield 21.8

(2) 88 grams /s mole) of (NH HPO were dis- Comparing Examples 2 and 3 of Table I with Examples solved in 500 cc.s of distilled water; 8 and 9 of Table II shows that the difference in catalyst Solution was Slowly added to SOIHtiOn (l) with calcining temperature had little effect. Examples 10-12 in vigorous stirring and the pH decreased as a white pre- Table II show various aryl halide charge stocks can be cipitate was formed. A minimum of pH of 1.4 was ate l d f ll tained and upon continued addition of the phosphate solution the pH began to increase. After all of the solu- Example 13 tion (2) was added, the pH was 2.7 (total time of addition The catalyst of Example 1 was employed using the same was 30 minutes); conditions as Example 3 for the hydrolysis of 2-chlo1'o- (4) NH OH solution was then added to adjust the pH para-xylene. After 120 minutes of reaction time the seto 6.0; lectivity, conversion and yield of hydroxylated xylene iso- (5) The precipitate was then separated from the mother mers (mostly 2-hydroxyl-para-xylene) was 95.5, 30.2 and liquor by filtration and was washed on the filter with 28.8 weight percent respectively. After five hours the coneight liters of water; version and selectivity were 27.0 and 91.8 weight percent (6) The precipitate was removed from the filter and respectively, resulting in a yield of 24.8 weight percent. grilled for 18 hours in moving air in an oven at 120 C.; Example 14 (7) The dried sample was calcined in air at 500 C. The catalyst for this example was prepared in a manner for 16 hours. The surface area of the calcined product similar to that for Example 1 above except the lanthanum was 136 mP/gram. to phosphorus ratio in the starting solutions was 111.5

In this and the other examples the mixing was in a and the pH of the initial diammonium hydrogen phospolyethylene vessel with stirring with Teflon coated prophate solution was adjusted to 9.5 using NH OH. The peller-type stirrers. minimum pH during addition of the phosphate source was A series of runs was made using the catalyst of Ex- 2.4 and the pH after the addition of the phosphate was ample 1 which was calcined at 500 C. for the conversion 6.0 without the need for adjustment. The surface area of o-chlorotoluene at varying reaction conditions. The of the dried and calcined catalyst was 114 square meters catalyst was regenerated between runs by burning in air per gram. at the reaction temperature. The results are summarized Example 15 in Table below The catalyst of Example 14 was employed for the hy- Refeinng tO.Tab1e I below It can seen :[hat an drolysis of 2-chloro-para-xylene under the same condicrease i reactlon tempfgrature resims m an Increase m tions as in Example 13. After 120 minutes the conversion converslon (cmPare.E}amp1e 6 h Examples 3 and and selectivity to the formation of a mixture of the various 2). The product in this example and in the other examples hydroxylated Xylene isomers was 18.7 and 92.4 Weight in this application where a monochlorotoluene was used percent respectively for a yield of 17.3 Weight percent. as the charge.stock was a nnXtur.e.of i .vanous hydroxyl' In all examples where a monochloroxylene was used as ated toluene isomers. The selectivity is higher at the lower the charge Stock, the product was a mixture of thc various temperatures' h drox lated x lene isomers Catalysts similar to that of Example 1 were prepared y y y except the pH of the phosphate source was adjusted over Example 16 The Tang? f t 8-3 and these catalysts were found Example 15 was repeated except the temperature was to be active for the hydrolysis of aryl halides. reduced to 460 C. and the LHSV was reduced to 0.148.

9 The conversion and selectivity after 120 minutes were 22.3 and 93.3. weight percent respectively, for a yield of 20.8 weight percent. After six hours the conversion, selectivity and yield were 21.0, 93.4 and 19.6 weight percent respectively.

Example 17 The preparation of the catalyst for this example was similar to the preparation for the catalyst of Example 1 except cerium nitrate was used in place of lanthanum nitrate. The pH of the initial cerium nitrate solution was 3.8. The surface area of the dry and calcined catalyst was 111 square meters per gram.

Example 18 The catalyst of Example 17 was employed for the hydrolysis of o-chlorotoluene using the same conditions as in Example 2 above. The conversion, selectivity and yield of methylphenols where 11.0, 74.4 and 8.2 weight percent respectively.

Example 19 This catalyst preparation was very similar to that for Example 14 above except the lanthanum to phosphorus ratio was 1:2 and the pH of the solution after the addition of all of the phosphate was 7.0, which was not thereafter adjusted. The surface area of the dried and calcined catalyst was 101 square meters per gram.

Example 20 The catalyst of Example 19 was employed for the hydro lysis of 2-chloro-para-xylene under the conditions of Example 15. The conversion and selectivity to the formation of the hydroxylated xylene isomers was 21.8 and 90.0 weight percent respectively, for a yield of 19.6 weight percent.

A lanthanum phosphate catalyst was made using H PO as the phosphate source, but the activity of this catalyst for the hydrolysis of ortho-chlorotoluene was lower than LaPO catalysts prepared from NH H PO or (NH HPO Example 21 A mixed lanthanum-cerium phosphate catalyst was prepared by:

1) Dissolving 130 grams of La(NO -6H O in 1500 cc.s of water (pH=6.9);

(2) Dissolving 14 grams of Ce (NO 6H O in 500 cc.s of distilled water (pI-I=3.6);

(3) The solutions of (1) and (2) were admixed (pH=5.6) which was further diluted to 5 liters (pH adjusted to 4.5 using HNO (4) Dissolving 88 grams of (NH H-PO in 2000 cc.s of distilled water with stirring. The pH of the phosphate solution was 8.1 and was adjusted to 9.3 with NH OH;

(5) The phosphate solution was slowly added to the La-Ce, salt solution while stirring constantly. A precipitate formed. The minimum pH was 3.9 and the final pH was 6.0 after 1500 cc.s of the phosphate solution were added (volume addition stopped at this point);

(6) The precipitate was filtered and washed with six liters of distilled water; and

(7) The precipitate was dried overnight at 120 C. and then calcined overnight at 500 C.

Example 22 The catalyst of Example 21 was employed for the hydrolysis of 2-chloro-para-xylene at 475 C., an LHSV of 0.291 and a time of two hours. The conversion was 13.1 percent; the selectivity was 96.6, for a yield of 12.7 percent.

Example 23 The catalyst for this example was prepared was prepared using a mixture of rare earth metal nitrates. The mixture of rare earth metal nitrates was cerium rich and contained the following weight percent rare earth metals:

28.0 percent lanthanum, 38.9 percent cerium, 3.7 percent praseodymium and 11.0 percent Nd. The preparation was similar to that for Example 1 above except an aqueous mixture of the rare earth metal nitrates was employed, the initial pH of the aqueous rare earth metal was 5.1 and the pH of the solution when all of the diammonium hydrogen phosphate was added was 3.4 and was thereafter adjusted to a pH of 6.0 using NH OH. The surface area of the catalyst after drying and calcining at 500 C. for 16 hours was 138 square meters per gram.

The catalyst of Example 23 was employed in a series of runs under varying conditions to hydrolyze 2-chl0ropara-xylene. The results are summarized in Table Ill below.

TABLE III Hydrolysis of 2-chloro-para-xylene using a mixed rare earth metal phosphate rich in cerium Example number 24 25 26 27 Temperature, C 475 475 450 500 Volume ratio of liquid H2O to liquid aryl halide 2 2 2 2 LHSV 0. 291 0. 146 0.146 0.582 Time, minutes 180 180 240 120 Results:

Conversion, wt. percent 5. 2 16. 0 9. 1 5. 5 Selectivity to xylenols, wt. percent- 93. 5 90.3 92. 8 72. 9- Yield of xylenols, wt. percent 4. 8 14. 4 8.4 4.0

The catalyst of Example 23 was employed in a second series of runs under varying conditions to hydrolyze o-chlorotoluene to form a mixture of methylphenols. The results are summarized in Table IV below.

TABLE IV Hydrolysis of o-clilorotoluene using a mixed rare earth metal phosphate rich in cerium Example number 28 29 30 Temperature, C 500 475 475 Volume ratio of liquid H2O to liquid aryl halide. 2 2 2 LHSV 0. 291 0. 291 0. 148 Time, minutes 180 180 180 Results:

Conversion, wt. percent 11. 2 7. 2 12. 6

Selectivity, wt. percent 86.3 94. 2 91. 0

Yield, wt. percent 9. 7 6. 7 11. 5

Example 31 121.7 in the initial solutions, the initial pHs of the rare TABLE V Hydrolysis of 2'cl1l0r0para-xylene using a mixed rare earth metal phosphate rich in lanthanum Example number 32 33 Temperature, O 475 460 Volume ratio liquid H2O to liquid aryl halide.-. 2 2 LHSV O. 148

Yield, wt. percent 11. 4 13. 0

Examples 23-33 show that mixtures of rare earth metal phosphates can be employed in the process of the subject invention.

1 1 Example 34 The catalyst preparation of Example 1 was repeated except neodymium nitrate was employed in place of the lanthanum nitrate. The pH of the neodymium nitrate solution was 4.9. The surface area of the dried catalyst calcined at 500 C. was 105 square meters per gram.

Example 35 The catalyst of Example 34 was utilized for the hydrolysis of chloro-para-xylene under the conditions of Example 3. The conversion of the chloro-para-xylene was 9.2 weight percent with a selectivity to the production of xylenols being 100 weight percent.

Example 36 Example 37 The catalyst of Example 36 was used for the hydrolysis of chloro-para-xylene under the same conditions as Example 3 above. The weight percent conversion was 11.4 and the selectivity was 94.6.

Example 37 shows that rare earth metal chlorides can be employed in place of rare earth metal nitrates.

Example 38 The catalyst for this example was prepared in a manner similar to that for Example 1 above except disodium hydrogen phosphate was used as the phosphate source. The pH of this solution was 8.9. The pH of the solution after the addition of all the phosphate was 3.3 and the final pH was adjusted to 6.5 using NH OH.

Example 39 The catalyst of Example 38 was tested for the hydrolysis of chloro-para-xylene under the same conditions as EX- ample 3 above except the time was 90 minutes. The weight percent conversion was 7.8 with 97.7 weight percent selectivity to the formation of the desired hydroxylated compounds.

Example 40 The catalyst for this example was prepared in a manner similar to that for Example 38 except trisodium phosphate was used as the phosphate source which had an initial pH of 12.7. The pH after the addition of the phosphate source was 8.0 which was not thereafter adjusted. The molar ratio of lanthanum to phosphorus was 1:1.3.

Example 41 The catalyst of Example 40 was tested for the hydrolysis of chloro-para-xylene under the same conditions of Example 39. Conversion was 3.3 weight percent and the selectivity was 90.3 weight percent.

Example 42 The catalyst for this example was prepared by mixing together in a dry state 144 grams of powdered and 39 grams of (NH HPO A small amount of water was added sufiicient to form a paste which was stirred to insure an intimate admixture of the salts. The paste was dried in an oven at 120 C. in moving air and was stirred frequently during the drying step. The dried product was calcined at 500 C. for 16 hours.

1 2 Example 43 A 10-20 mesh sieved sample of the catalyst of Example 42 was tested for the hydrolysis of chloro-para-xylene at 460 C.; a water to chloro-para-xylene volume ratio of 2:1; a liquid hourly space velocity of 0.148 and a reaction time of two hours. The conversion was 11.2 weight percent and the selectivity was only 56.4 percent.

A comparison of Examples 42 and 43 with the other examples in this specification show that other methods of preparation of the rare earth metal phosphates can be employed.

Example 44 The catalyst for this example was prepared as follows:

(1) 144 grams of La(NO -6H O were dissolved in five liters of water (pH=5.9 and was adjusted to 4.5 with HNO (2) 78 grams of H PO percent) was added to two liters of water and the pH was adjusted to 8.7 with NH gas. The total volume of this solution was 2030 cc.s;

(3) 500 cc.s of water and 500 cc.s of the lanthanum nitrate solution were placed into a mixing vessel. The pH of this solution was 4.5;

(4) The phosphate solution was added slowly to the solution in the mixing vessel with vigorous stirring and the pH decreased slowly as a white precipitate was formed. A minimum pH of 2.15 was attained, after which the pH began to increase;

(5) When a pH of 3.0 was reached, the lanthanum nitrate solution and the phosphate solution were added simultaneously and the relative rates of addition were adjusted to main the pH constant at 3.0 until all of the lanthanum nitrate solution was added. The slurry in the mixing vessel was stirred vigorously to minimize pH gradients during the entire addition step;

(6) After all of the lanthanum nitrate solution was added, the addition of the phosphate solution was continued until the pH reached 6.5. At this point, 1770 cc.s of the phosphate solution had been used, and this corresponds to a ratio of LazP of 121.75 in the final mixed slurry;

(7) The precipitate was separated by filtration and was washed on the filter with six liters of water;

(8) The filter cake was broken into suitable sized pieces and dried in moving air at C. for 16 hours; and

(9) The dried catalyst was calcined at 500 C. in air for 16 hours.

Example 45 The catalyst of Example 44 was tested for the hydrolysis of 2-chloro-para-xylene at 475 C., a liquid hourly space velocity of 0.291, a water to 2-chloro-para-xylene volume ratio of two and for a time of two hours. The conversion of 2-chloro-para-xylene was 16.8 weight percent with a selectivity to the formation of xylenols of 96.8 weight percent. The yield of the xylenols was therefore 16.3 percent.

Example 46 The catalyst for this example was prepared as follows:

(1) 720 grams of La(NO -6H O were dissolved in 25,000 cc.s of water and the pH was adjusted to 4.7 with HNO (2) 255 grams of H PO (85 percent) were diluted to 12,500 cc.s with water and the pH was adjusted to 8.7 by bubbling NH gas into the solution;

(3) 1500 cc.s of water were placed into a mixing vessel (about 15 liters) and 25 cc.s of the solution was added;

(4) The phosphate solution was added slowly with stirring together with a small amount of additional lanthanum nitrate solution as needed until the pH of the mixed solutions reached 3.0;

(5) The lanthanum nitrate and phosphate solutions were then added simultaneously at substantially constant rates of about 200 cc./min. and 100 cc./min. respectively; the pH was maintained constant at about 3.0 by adding -NH gas as needed;

(6) When the mixing vessel became nearly full, about 8250 cc.s were withdrawn to a holding vessel while the addition of the two solutions to the mixing 'vessel was continued (this withdrawl procedure was actually used five times until all of the starting solutions had been added to the mixing vessel);

I (7) The pH of the portions removed to the holding vessels was adjusted immediately to 6.5 with NH gas and the precipitate was separated by filtration and Washed on the filter with water;

(8) The filter cake from each of the five filters was broken up and the pieces were admixed and dried in moving air in an oven at 120 C. for 16 hours; and

(9) The dried catalyst was calcined at 500 C. for 16 hours.

A series of runs was made using the catalyst of Example 46 tor the hydrolysis of 2-chloro-para-xylene. The results are shown in Table VI below.

The preparation of the catalyst of Example 46 was repeated except the calcination temperature was 600 C.

A series of runs was made using the catalyst of Example 53. for the hydrolysis of 2-chloro-para-xylene. The results are shown in Table VII below.

TABLE VII Hydrolysis of 2-chloro-para-xylene to 2-hydroxy-para-xylene Conver- Selec- H2O/Og sion, tivit-y, Ex. Temp., volume Time, wt. wt. No. 0. ratio LHSV hours percent percent 475 1 0. 296 2 31. 2 87. 7

A second series of runs was made using the catalyst of Example 53 using different charge stocks. The results of these runs are shown in Table VIII below.

In the preparation of the catalyst for Example 46, the rate of addition of the lanthanum and phosphate solutions in step (5) was 200 cc./min. and 100 cc./min. respectively. This resulted in a La/P mole ratio of 1:1.18. Additional preparations were made where the La/P ratio was maintained at 1:1.18 and Where the rate of addition of the lanthanum solution varied from 90 to 500' cc./min. while the rate of addition of the phosphate solution varied accordingly from 45 to 250 cc./min. The volume ratio of the lanthanum to phosphate solution was, of course, maintained at about 2:1. In general, the more active catalysts were prepared using the higher rates of addition.

Example The catalyst for this example was prepared as follows:

(1) 144 grams of La(NO' '6H O were dissolved in two liters of water;

(2) 40 grams of urea (NHgCONH were dissolved in two liters of water;

(3) Solutions (1) and (2) were combined and water was added to bring the total volume to five liters (the pH of the combined solution was 5.53);

(4) 45 grams of H PO percent) were diluted to 2% liters with water (pl-1:146);

(5) The lanthanum-urea solution and the phosphoric acid solution were added slowly, with stirring, to a mixing vessel containing one liter H O. The pH decreased quickly as a white precipitate was formed;

(6) When the pH reached 3.0, the two solutions were added simultaneously at the rate of 200 cc./min. and cc./min. respectively and NH gas was added as needed to maintain a constant pH of 3.0;

(7) The mixing zone was stirred vigorously to minimize pH gradients. After both solutions had been exhausted, stirring was continued for five minutes, and the pH of the mixed slurry was 3.2. (The LazP ratio in the final mixed slurry was 1:1.18, based upon the composition of the solutions used in the preparation);

(8) NIIg gas wa added until the pH reached 6.2, after which the precipitate was separated by filtration. The precipitate was washed on the filter with one liter water and the filter cake was dried at C. for 16 hours; and

(9) The dried precipitate was calcined in air at 500 C. for 16 hours.

Example 71 The catalyst of Example 70 was used for the hydrolysis of Z-chloro-para-xylene using a water to charge stock volume ratio of 1:1; a liquid hourly space velocity of 0.296 based, as usual, on the 2-chloro-para-xylene; for a time of two hours; and a temperature of 450 C. The conversion of 2-chloro-para-xylene was 14.2 weight percent; the selectivity to xylenols was 97.6 weight percent, for a yield of xylenols of 14 percent.

In another aspect of this invention, an aryl halide as defined above is hydrolyzed to produce a ring hydroxyl substituted aryl compound by a process which comprises contacting the aryl halide in the presence of water under hydrolysis conditions with a catalyst comprising at least TABLE VIII charge Conver- Selecstock sion, tivity, Temp, volume LHSV, Time, weight weight Example No. Charge stock ratio v./v./h1 hours percent percent 2-chloro-p-xylene 425 1 0. 296 2 19. 6 100 65 o-Chlorotoluene- 425 1 0. 296 2 13. 6 100 425 1 0. 296 2 14. 6 100 425 1 0. 296 2 15. 3 100 425 1 0. 296 2 10. 1 100 450 1 0. 296 2 26. 8 100 Other catalysts were made in a manner similar to the continuous procedure of Example 46 except the pH of the phosphate solution was from 6.0 to 9.0 and the con stant pH maintained during precipitation varied from a low of about two to a high of five and active catalysts for the hydrolysis of 2-chloro-para-xylene were obtained. 75 rare earth metal phosphate of this invention and yttrium one metal phosphate selected from the group consisting of a rare earth metal phosphate and yttrium phosphate and at promoting amount of copper.

It has been found quite surprisingly that very small amounts of copper will greatly promote the activity of the phosphate for the hydrolysis of aryl halides. For example, it has been found that as little as 200 p.p.m. (parts per million parts by weight of catalyst) of copper added to a LaPO catalyst has increased the conversion of Z-chloropara-xylene six-fold with little loss in selectivity at 400 C. The addition of 10,000 p.p.m. of copper has resulted in similar increases in conversion but the selectivity decreases. A suitable range of copper content is from about 50 to about 10,000 p.p.m. by weight of the catalyst, with the preferred copper content being from about 100 to 2500 p.p.m. by weight of the catalyst.

The copper can be added to the yttrium or rare earth metal phosphate by any suitable procedure. The particular method of addition of the copper does not appear to be critical. For example, the copper can suitably be added to a preformed lanthanum phosphate catalyst by impregnation of the lanthanum phosphate with a solution, preferably aqueous, of a suitable copper salt such as copper nitrate. Other copper salts can also be employed, such as copper acetate, copper chloride and copper sulfate, but are not as preferred since it is more difficult to remove the anion portions. The copper promoted catalyst can also suitably be prepared by coprecipitating the copper with yttrium or the rare earth metal during the preparation of the yttrium or rare earth metal phosphate. The yttrium phosphate can suitably be prepared by the same procedures described above for the rare earth metal phosphates using yttrium salts such as yttrium nitrate or yttrium chloride. Thus, a copper salt, preferably copper nitrate, can be added in any desired concentration to the solution of the yttrium or rare earth metal salt, i.e., lanthanum nitrate, and then precipitating the yttrium or rare earth metal phosphate by any suitable method, such as those disclosed earlier in this specification. The copper will precipitate together with the yttrium or rare earth metal and become incorporated into the final compositron.

The final composition should then be dried and calcined as noted above.

This aspect of the invention is illustrated by the following experimental work.

Example 72 The catalyst of this example was prepared as follows:

(1) 288 grams of La(NO -6H O was dissolved in ten liters of distilled water. The pH of this solution was 5.3 and this was adjusted to 4.7 by the addition of HNO (2) 90 grams of H PO was mixed with five liters of distilled water. The pH of this solution was 1.45 and was adjusted to 8.7 by bubbling in NH gas.

(3) 1500 ccs of distilled water was added to a polypropylene mixing vessel and solutions (1) and (2) were added slowly, with vigorous stirring, in proportions which were adjusted to yield a pH of 3.0 in the mixing vessel. When a pH of 3.0 was attained, solution (1) was added at the rate of 200 cc./min and solution (2) at the rate of 100 cc./min., with vigorous stirring. The pH of the mixing zone was monitored and maintained at a constant value of 3.0 by bubbling in NH gas as needed.

When solutions (1) and (2) were exhausted, NH gas was bubbled into the slurry until the pH reached 6.2. The precipitate was then separated by filtration and washed on the filter with two liters of distilled water, the pH of which was 6.1.

The filter cake was broken into chunks and dried in moving air at 120 C. for approximately hours. The dried product was then calcined in air at 500 C. for 16 hours.

Example 73 Example 71 was repeated except the catalyst of Example 72 was used and the reaction temperature was reduced to 400 C. The conversion of 2-chloro-para-xylene was only 2.6 weight percent and the efiiciency to the formation of xylenols was 100 percent for a yield of 2.6 weight percent. The results are shown in Table IX below.

A series of catalysts was prepared by impregnating the catalyst of Example 72 with an aqueous solution of copper nitrate using the method of incipient wetness to deposit the following nominal amounts of copper: 200 p.p.m. and 10,000 p.p.m. The catalysts were dried and then calcined for 24 hours in air at 600 C. The catalysts were tested in the same manner as Example 73, and the results are shown in Table IX below.

Referring to Table IX below, it can be seen that the addition of only 200 p.p.m. of copper increases the conversion sixfold with little loss in selectivity (compare Examples 73 and 74) while the addition of 10,000 p.p.m. of copper results in the same increase in conversion but the selectivity is reduced (Example 75).

TABLE IX.HYDROLYSIS on 2-Cl-ILORO-PARA-XYLENE [Conditions: 400 0., 0.296 volumes of xylene per volume of catalyst per hour, a volume ratio of water to xylene 0t 1, atmospheric pressure for 2 hours] Rare earth Conver- Selee- Yield,

111 Copper, sion, wt. tivity, wt. wt.

Ex. No. phosphate p.p.m. percent percent percent 73 LaPO; 0 2.6 100 2.6

74 LaPO4 200 18.3 95 17.4

75 LaPO4 10, 000 20.2 54 10. 9

Example 76 The catalyst for this example was prepared in the same manner as the catalyst for Example 72 except 2000 cc.s of distilled water was used in the mixing vessel initially and the rate of addition of solution (1) and solution (2) after the pH of 3.0 was attained was 500 cc./min. and 250 cc./min. respectively.

Example 77 Example 71 was repeated except the catalyst of Example 76 was used and the reaction temperature was 425 C. The conversion of 2-chloro-para-xylene was 9.8 weight percent and the selectivity to the formation of xylenols was 98.0 weight percent, for a yield of 9.6 weight percent. The results are shown in Table X below.

Example 78 TABLE X.HYDROLYSIS OF Z-CHLORO-PARA-XYLENE [Conditions: 425 C., 0.296 volumes of xylene per volume of catalyst per hlour, 21 volume ratio of water to xylene of 1, atmospheric pressure for 2 101115 Rare earth Conver- Selec- Yield,

metal Copper, sion, wt. tivlty, wt. wt.

Ex. No. phosphate p.p.rn. percent percent percent 77 LaPO4 0 9.8 98 9.6

78 LaPOi 200 22.3 98 21.8

Example 79 The catalyst of this example was prepared in the same manner as the catalyst for Example 76 except 0.05 grams of ferric nitrate (Fe(NO -9H O) in aqueous solution was added to the lanthanum nitrate solution.

Example 80 Example 77 was repeated except using the catalyst of Example 79. In addition, the reaction time was only one hour. The conversion of 2-chloro-para-xylene was 8.6 weight percent. The selectivity to the formation of xylenols was 98.6 weight percent, for a yield of 8.5 weight percent.

EXAMPLE 81 The catalyst of Example 80 was regenerated by heating at 460 C. for 1.5 hours in a flow of air. After the catalyst cooled, it was impregnated with an aqueous solution of copper nitrate by the method of incipient wetness to product a catalyst containing a nominal amount of copper in the amount of 200 ppm. The catalyst was dried at 250 'C. and calcined in air at 600 C. for one hour. This catalyst was run in the same manner as Example 80. The conversion of 2-chloro-para-xylene was 36.2 weight percent. The selectivity to the formation of xylenols was 96.3, for a yield of 34.9 weight percent.

A series of copper promoted catalysts were prepared by coprecipitating the copper and rare earth metal together from an aqueous solution of their nitrate salts using the technique of Example 79, except copper nitrate was used in place of ferric nitrate and the calcination temperature was in some cases 600 C. Sufiicient copper nitrate was used to give the nominal amounts shown in Table XI below. Each of these catalysts was tested for the hydrolysis of Z-chloro-para-xylene using the same conditions as Example 73. The results are shown in Table XI below.

18 EXAMPLE 9s (3) 2,000 cc.s of distilled water was added to a polypropylene mixing vessel and solutions (1) and (2) were simultaneously added with vigorous stirring at the rates of 500 cc.s and 250 cc.s per minute respectively while the pH was maintained at 3.0 by the addition of NH gas as needed;

TABLE XI.HYDROLYSIS OF Z-OHLORO-PARA-XYLENE [Conditions: 400 0., 0.296 volumes of xylene per volume of catalyst per hour, a volume ratio of water to xylene of 1; atmospheric pressure for 2 hours] Conver- Selec- Calcision, tivity, Yield, nation Ex. Rare earth Copper, wt. wt. wt. temp, N0. metal phosphate p.p.m. percent percent percent 0.

s2- LaPo. 120 19.6 99. 7 19. 5 50 83 240 26. 9 99. 1 26. 6 50 84- L 360 25.1 97. 9 24. 6 600 85- LaPO4 480 34. 3 98. 8 33. 9 600 86. LaPO4 750 33. 0 98. 3 92. 4 500 87- LaPO4 1, 000 37. 4 95. 7 35. 8 600 88. Lao oOen. PO4 0 7. 8 100.0 7. 8 600 89- L 480 25. 2 99. 0 24. 9 600 90- Mixed rare earths 480 29. 6 98. 7 29. 2 600 Mixture was the same as that defined and used in Example 23.

EXAMPLE 91 (4) When solution (1) and (2) were exhausted the Example 85 was repeated except meta-dichlorobenzene was used as the charge stock. The conversion of metadichlorobenzene was 13.6 weight percent; the selectivity to the formation of phenol and 2-chlorophenol was 73.9 weight percent, for a yield of 10 weight percent.

EXAMPLE 92 Example 85 was repeated except the reaction temperature reduced to 300 C. The conversion was reduced to three weight percent and the selectivity was 100 percent.

The catalyst of Example 85 was also employed for the hydrolysis of bromobenzene and for the hydrolysis of iodobenzene and lower conversions were realized. The chloroaromatics are thus the most preferred charge stocks for the process of this invention. A copper promoted lanthanum phosphate catalyst was also employed for the hydrolysis of 1,2,4-trichlorobenzene and 3,4-dichlorotoluene. The di and trichloro derivatives tended to form the monohydroxy products with the second and third chloro substitutents being replaced with hydrogen, especially at the higher temperatures. Apparently the first chloro group hydrolyzed slowly and any additional halogen groups are then more'quickly replaced with hydrogen.

EXAMPLE 93 The catalyst for this example was prepared in a manner similar to that for the catalyst of Example 1 except Y(NO -4H O was used in place of La(NO -6H O. In addition, the 88 grams of (NH HPO were dissolved in 1000 cc.s of water and the pH adjusted to 9.0 with NH OH. The minimum pH attained was 1.75 and the final pH of 6.0 was achieved using 890 cc.s.of the (NH HPO solution without further need of NH OH.

EXAMPLE 94 The catalyst of Example 93was employed for the hydrolysis of 2-chloro-para-xylene under the same conditions as Example 3. After 120 minutes, the conversion of 2-chloro-para-xylene was only 0.7 weight percent.

pH was adjusted to 6.16 by the addition of NH gas; and (5) The precipitate was filtered, washed with water, dried at 120 C. for 16 hours and calcined at 600 C. for 16 hours.

EXAMPLE 96 Example 94 was rerun. except using the catalyst of Example 95. The conversion was 20.9 weight percent; the selectivity was 97.8 weight percent; and the yield was 20.4 weight percent.

A comparison of Examples 94 and 96 show the effect of the addition of small amounts of copper on yttrium phosphate.

EXAMPLE 97 The catalyst preparation of Example was repeated except 146 grams of neodymium nitrate was used in place of the yttrium nitrate and 45 grams of H UO was added to 2500 cc.s of distilled water.

EXAMPLE 98 The catalyst of Example 97 was used for the hydrolysis of 2-chloro-para-xylene under the conditions of Example 57. The conversion was 25.4 weight percent; the selectivity was 99.6 weight percent, for a yield of 25.3 percent.

The results of Example 98 should be compared with the results of Example 35 which used a neodymium phosphate catalyst without copper and the conversion was about nine weight percent, even though the temperature was higher.

Example 99' TABLE XIL-HYDROLYSIS OF 2-CHLORO-PARA-XYLENE [Catalystz Cu promoted cerium phosphate] Selec- Reaction Convertivity, Yield, Ex. temp., sion, wt. wt. wt. Volume No. percent percent percent LHSV H' O/C Example 104 Example 100 was repeated except chloro-benzene was used in place of 2-chloro-para-xylene. The weight percent conversion, selectivity and yield of phenol were 23.7, 100 and 23.7 respectively.

Example 105 The catalyst preparation of Example 97 was repeated except no Cu(NO -3H O was added.

Example 106 The catalyst of Example 105 was used for the hydrolysis of 2-chloro-para-xylene under the conditions of Example 57. The conversion was 8.4 weight percent; the selectivity was 100 weight percent and the yield was 8.4 weight percent.

In one further aspect of this invention, it has been found that the presence of cerium in the rare earth metal catalysts appears to result in a faster rate of burnofi of coke during regeneration.

Resort may be had to such variations and modifications as fall within the spirit of the invention and the scope of the appended claims.

We claim:

1. A procem for the hydrolysis of an aryl halide to produce a ring hydroxyl substituted aryl compound which comprises contacting an aryl halide having a total of from 6 to carbon atoms and having from one to two aromatic rings, from one to six halide substituents directly connected to aromatic ring carbon atoms and wherein said halide substituents are selected from the group consisting of chlorine, bromine and iodine, and the remaining substituents on said aromatic ring carbon atoms are selected from the group consisting of lower alkyl groups, hydrogen and N0 in the presence of water under hydrolysis conditions wherein the aryl halide and water are in the vapor phase with a solid catalyst essentially consisting of at least one rare earth metal phosphate.

2. A process according to claim 1 wherein the aryl halide is a single-ring aromatic hydrocarbon having from one to two halide substituents and from 6 to 10 carbon atoms. I

3. A process according to claim 1 wherein the aryl halide has the formula:

where R R R R R and R are selected from the group consisting of chlorine, bromine, iodine, lower alkyl groups, hydrogen or N0 and where from one to three of said substituents is selected from the group consisting of chlorine, bromine or iodine.

4. A process according to claim 3 wherein one of the R groups is a halide selected from chlorine, bromine and iodine; from 0 to 2 of the R groups are lower alkyl groups and the remaining R groups are hydrogen.

5. A process according to claim 4 wherein the rare earth metal phosphate is an unsupported rare earth metal phosphate.

6. A process according to claim 5 wherein the aryl halide is a monochloroxylene.

7. A process according to claim 5 wherein the aryl halide is a chlorobenzene.

8. A process according to claim 5 wherein the catalyst comprises a mixture of rare earth metal phosphates containing at least some lanthanum phosphate.

9. A process according to claim 5 wherein the hydrolysis conditions include a temperature from 300 to 600 C.

10. A process according to claim 9 wherein the catalyst is prepared by admixing an aqueous solution of a rare earth metal salt and an aqueous solution of a phosphate ion source to form the rare earth metal phosphate at a pH level in the combined solutions of from 2.0 to 5.0.

11. A process according to claim 10 wherein the phosphate ion source has the formula:

where X can be NH or a monovalent alkali metal and where a has a value from 0 to 3 and b has a value of 3 minus a.

12. A process for the hydrolysis of an aryl halide to produce a ring hydroxyl substituted aryl compound which comprises:

contacting an aryl halide having the formula:

wherein one of the R groups is a halide selected from chlorine, bromine and iodine; from 0 to 2 of the R groups are lower alkyl groups and the remaining R groups are hydrogen;

in the presence of water under hydrolysis conditions including a temperature from 375 to 500 C. and a water to aryl hydrocarbon volume ratio of 0.1:1 to :1 and wherein the aryl halide and water are in the vapor phase with a solid unsupported catalyst essentially consisting of at least one rare earth metal phosphate.

13. A process according to claim 12 wherein the rare earth metal phosphate has the formula:

where Me is a metal having a valence of three and is selected from lanthanum, cerium, neodymium or mixtures thereof.

14. A process according to claim 13 wherein Me is lanthanum.

15. A process for the hydrolysis of monochlorotoluene to produce a ring hydroxyl substituted aryl compound which comprises contacting monochlorotoluene in the presence of water under hydrolysis conditions wherein the monochlorotoluene and the water are in the vapor phase with a solid unsupported catalyst essentially consisting of at least one rare earth metal phosphate.

16. A process for the hydrolysis of an aryl halide to produce a ring hydroxyl substituted aryl compound which comprises:

contacting an aryl halide having the formula wherein one of the R groups is a halide selected from chlorine, bromine and iodine; from to 2 of the R groups are lower alkyl groups and the remaining R groups are hydrogen;

in the presence of water under hydrolysis conditions including a temperature from 375 to 500 C. and a water to aryl hydrocarbon volume ratio of 0.1:1 to 100:1 and wherein the aryl halide and water are in the vapor phase;

with a solid unsupported catalyst essentially consisting of at least one rare earth metal phosphate having the formula:

MePO

where Me is a metal having a valence of three and is selected from lanthanum, cerium, neodymium or mixtures thereof.

17. A process according to claim 16 wherein the rare earth metal phosphate is lanthanum phosphate.

18. A process according to claim 16 wherein the rare earth metal is cerium.

19. A process for the hydrolysis of an aryl halide to produce a ring hydroxyl substituted aryl compound which comprises:

contacting the aryl halide having a total of from 6 to 20 carbon atoms and having from one to two aromatrc rings, from one to six halide substituents directly connected to aromatic ring carbon atoms and wherein said halide substituents are selected from the group consisting of chlorine, bromine and iodine and the remaining substituents on said aromatic ring carbon atoms are selected from the group consisting of lower alkyl groups, hydrogen and N0 1n the presence of water under hydrolysis conditions wherein the aryl halide and water are in the vapor phase with a solid catalyst essentially consisting of at least one metal phosphate selected from the group consist- 1ng of a rare earth metal phosphate and yttrium phosphate and a promoting amount of copper.

20. A process according to claim 19 wherein th 1 halide has the formula: 6 my wherein one of the R groups is a halide selected from chlorine, bromine and iodine; from 0 to 2 of the R groups are lower alkyl groups and the remaining R groups are hydrogen, and wherein the rare earth metal phosphate is unsupported.

21. A process according to claim 20 wherein the solid catalyst consists of at least one rare earth metal phosphate.

22. A process according to claim 20 wherein the amount of copper is less than 10,000 p.p.m. by weight of the catalyst.

23. A process according to claim 22 wherein the amount of copper is from about 50 to about 2500 parts per million by weight of the catalyst.

24. A process for the hydrolysis of an aryl halide to produce a ring hydroxyl substituted aryl compound which comprises:

contacting an aryl halide having the formula:

wherein one of the R groups is a halide selected from chlorine, bromine and iodine; from 0 to 2 of the R 22 groups are lower alkyl groups and the remaining R groups are hydrogen in the presence of water under hydrolysis conditions wherein the aryl halide and water are in the vapor phase with a solid unsupported catalyst essentially consisting of yttrium phosphate and a promoting amount of copper.

25. A process for the hydrolysis of an aryl halide selected from the group consisting of chlorobenzene, a chlorotoluene or a chloroxylene which comprises contacting the aryl halide in the presence of water under hydrolysis conditions with a catalyst essentially consisting of at least one rare earth metal phosphate and a promoting amount of copper.

26. A process according to claim 25 wherein the catalyst is an unsupported rare earth metal phosphate catalyst containing from to 1000 parts per million by weight of copper.

27. A process for the hydrolysis of an aryl halide to produce a ring hydroxyl substituted aryl compound which comprises:

contacting an aryl halide having the formula:

Ra Ra wherein one of the R groups is a halide selected from chlorine, bromine and iodine; from 0 to 2 of the R groups are lower alkyl groups and the remaining R groups are hydrogen in the presence of water under hydrolysis conditions wherein the aryl halide and water are in the vapor phase with a solid unsupported catalyst consisting of Ianthanum phosphate and a promoting amount of coper. 28. A process for the hydrolysis of an aryl halide to produce a ring hydroxyl substituted aryl compound which comprises:

reacting an aryl halide having a total of from 6 to 20 carbon atoms, from one to two aromatic rings and from one to six halide substituents directly connected to aromatic ring carbon atoms, said halide substituents being selected from the group consisting of chlorine, bromine and iodine, and the remaining substituents on said aromatic ring carbon atoms are selected from the group consisting of lower alkyl groups, hydrogen and N0 with water under hydrolysis conditions wherein the aryl halide and water are in the vapor phase in the presence of a solid catalyst consisting of at least one rare earth metal phosphate.

References Cited UNITED STATES PATENTS 1,321,271 11/1919 Zollinger et a1. 260--629 1,882,825 10/1932 Hale et a1. 260629 1,882,824 10/ 1932 Hale et al 260629 1,950,359 3/1934 Jenkins et al 260629 2,988,573 6/1961 Sibentrill et a1. 260629 3,234,291 2/ 1966 Kelly 260629 BERNARD HELFIN, Primary Examiner W. B. LONE, Assistant Examiner US. Cl. X.R.

260623 R, 622 R, 620, 619 R 5 mg 01mm smrss mrmr OFFHCE "CER'NFYQATE @F fiURRECTKON 3,838,182 September 24, 1974 Patent No. Dated Inventor) William L. Kehl and Raymond J. Rennard, Jr.

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 7, line 1, "is" should be --it-;

Col. 9, line 72, "was prepared was prepared" should be --was prepared--;

Col. 12, line 33, "main" should be --maintain--;

Col. 13, Table'VI, 3rd line under "Conversion, wt

"16.5" should be --l5.5-;

Col. 13, line 47, Table VII, first Example No., I

""45" should be ----54---;

Col. 17, line 2 "to product" should be --to produce-;

Col. 17, Table XI, under "Yield wt. percent" across from Example 86, "92.4" should be --32.4--;

Col. 18, lllle 52, H UO should be H PO Signed and sealed this 28th day of January .1975.

(SEAL) Attest:

MCCOY M. GIBSONJR. I i c. MARSHALL DANN Attesting Officer 7 Commissioner of Patents 

